You should be able to pledge this now.
The S&P fund you’ve spoken about was allowed by the exchange from this month. Hence, we update our approved list of securities at the start of every month. MF’s are added after confirming the market-wide limit and the member-specific security limits. There are a few other checks we perform in the backend before allowing any security to pledge. You can expect new securities to be added by the 2nd or the 3rd working day of every month.